1. Field of the Invention
The invention relates to a parking lock device for a vehicle.
2. Description of Related Art
For example, Japanese Patent Application Publication No. 2013-151981 (JP 2013-151981 A) describes a technology related to a conventional parking lock device for a vehicle. JP 2013-151981 A discloses a control apparatus for a continuously variable transmission (CVT) disposed in a vehicle in order to reduce an impact that occurs in a parking lock mechanism when shifting means is switched from a movable position to a parking position.
The control apparatus for the continuously variable transmission disclosed in JP 2013-151981 A includes the parking lock mechanism that is switchable between a restricted state in which the rotation of drive wheels is restricted and a movable state in which the rotation of the drive wheels is permitted. The parking lock mechanism includes a parking rod, a parking cam, a cam guide, and a parking pawl. The parking cam is disposed on the parking rod so as to be slidable relative to the parking rod. The parking cam is supported by the cam guide so as to be slidable in the axial direction of the parking rod. The parking pawl is provided with an engagement protrusion that is engageable with a parking gear, and the parking pawl is urged in a direction away from the parking gear by elastic force of a return spring.
When the parking cam enters the cam guide in response to actuation of the parking lock mechanism, the parking cam presses the parking pawl. Thus, the parking pawl moves to approach the parking gear against the elastic force of the return spring. As a result, the engagement protrusion is engaged with the parking gear, and thus the parking gear is locked.
In the parking lock mechanism disclosed in JP 2013-151981 A, the parking cam is provided with a tapered portion, along which the parking pawl moves to approach the parking gear. In the movable (unlocked) state in which the rotation of the drive wheels is permitted, the tapered portion and the cam guide are in contact with each other, so that the parking cam is supported.